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    <script>
        function myInstanceOf(left, right) {
            let leftVale = left.__proto__;
            let rightVale = right.prototype;
            // console.log(leftVale)
            // console.log(rightVale)
            while (true) {
                if (leftVale == rightVale) {
                    return true;
                } else if (leftVale == null) {
                    return false;
                }
                leftVale = leftVale.__proto__;
            }
        }
        let arr = [1, 2, 3, 4, 5, 6];
        console.log(myInstanceOf(arr, Object))
    </script>
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